<template>
  <el-container>
    <!-- 头部区域 -->
    <el-header>
      <div>
        <img src="../assets/heima.png" alt>
        <span class="title">电商后台管理系统</span>
      </div>
      <el-button type="info" @click="logout">退出</el-button>
    </el-header>
    <!--主体区域 -->
    <el-container>
      <!-- 左侧侧边栏区域 -->
      <el-aside :width="isCollapse ? '64px' : '200px'">
        <div class="toggle-button" @click="toggleCollapse">|||</div>
        <!-- 菜单区域 -->
        <el-menu
          background-color="#333744"
          text-color="#fff"
          active-text-color="#5067DB"
          unique-opened
          :collapse="isCollapse"
          :collapse-transition="false"
          router
          :default-active="activeIndex"
        >
          <!-- 一级菜单 -->
          <el-submenu :index="item.id + ''" v-for="item in menuList" :key="item.id">
            <!-- 一级菜单模板 -->
            <template slot="title">
              <!-- 图标 -->
              <i :class="iconList[item.id]"></i>
              <!-- 文本 -->
              <span>{{item.authName}}</span>
            </template>
            <!-- 二级菜单 -->
            <el-menu-item
              :index="'/' + subItem.path"
              v-for="subItem in item.children"
              :key="subItem.id"
              @click="saveActiveIndex('/' + subItem.path)"
            >
              <i class="el-icon-menu"></i>
              <span>{{subItem.authName}}</span>
            </el-menu-item>
          </el-submenu>
        </el-menu>
      </el-aside>
      <!-- 右侧主体区域 -->
      <el-main>
        <router-view></router-view>
      </el-main>
    </el-container>
  </el-container>
</template>
<script>
export default {
  created() {
    this.getMenuList()
    this.activeIndex = window.sessionStorage.getItem('activeIndex')
  },
  data() {
    return {
      /* 储存左侧菜单信息 */
      menuList: [],
      /* 左侧菜单图标列表 利用id值唯一设定对应图标(已知id值) */
      iconList: {
        125: 'iconfont icon-users',
        103: 'iconfont icon-tijikongjian',
        101: 'iconfont icon-shangpin',
        102: 'iconfont icon-danju',
        145: 'iconfont icon-baobiao'
      },
      /* 控制是否展开菜单 */
      isCollapse: false,
      /* 被激活的链接 */
      activeIndex: ''
    }
  },
  methods: {
    /* 退出功能 */
    logout() {
      window.sessionStorage.clear()
      this.$router.push('/login')
    },
    /* 获取左侧菜单信息 */
    async getMenuList() {
      const { data: res } = await this.$http.get('/menus')
      if (res.meta.status !== 200) return this.$message.error(res.meta.msg)
      this.menuList = res.data
    },
    /* 改变左侧菜单栏展开状态 */
    toggleCollapse() {
      this.isCollapse = !this.isCollapse
    },
    /* 保存被激活链接 */
    saveActiveIndex(activeIndex) {
      window.sessionStorage.setItem('activeIndex', activeIndex)
      this.activeIndex = activeIndex
    }
  }
}
</script>
<style lang="scss" scoped>
.el-container {
  height: 100%;
}
.el-header {
  background-color: #373d41;
  display: flex;
  justify-content: space-between;
  padding-left: 0;
  align-items: center;
  font-size: 20px;
  color: #fff;
  div {
    display: flex;
    align-items: center;
    span {
      margin-left: 10px;
    }
  }
}
.el-aside {
  background-color: #333744;
  .el-menu {
    border-right: 0;
  }
}
.el-main {
  background-color: #eaedf1;
}
.iconfont {
  margin-right: 10px;
}
.toggle-button {
  color: #fff;
  text-align: center;
  font-size: 10px;
  letter-spacing: 0.2em;
  line-height: 30px;
  cursor: pointer;
  background-color: #4a5064;
}
</style>
